When I worked as a tool and model maker, I made a set of bushings out of loop style GP so I could put the fast pin type GP in a 190D. They worked great. I shunted the firewall resistor and replaced the in- dash indicator resistor with a copper wire. I just had to guess at the time needed to energize the GP. The original pull starter and GP switch was used without modifications.

It is highly unlikely that all the loop style GP were bad. If the last one was bad or the ground connection open, they would all test bad the way there were tested. I would investigate further.

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